So I have an m6 Gran coupe. Iím not interested in lowering at the moment, not until I move in the next year or so. Believe it or not, the only driveway Iíve ever scraped on is my own, itís super steep, not ideal for car enthusiast lol.

I also donít want to buy new wheels and like the look of my factory 601m comp package wheels powder coated gloss black. Those wheels are a 20x9.5 front and 20x10.5 rear. My tires are stock size MPS4s, which is 265/35/20 front and 295/30/20 rear.

So, since Iím not lowering it and I donít wanna buy new wheels, whatís the widest tire I can run and what size wheel spacer should I get with that tire to be flush?

To break down that question a bit more:

For the fronts, do I keep stock size tires? Is there any benefit to going to 275s? Any negatives? Iím guessing 285s wonít fit can somebody confirm this.

I was told wheel spacers in the front can cause a lot of issues so should I just not bother with front wheel spacers?

In the rear I was told 305/30/20 is the best size to run and 315s arenít really available with a good aspect ratio on MPS4s for the stock wheels, is this true?

Without lowering, whatís the best size spacer to run in the rear with 295/30s? With 305/30s?

Donít touch the front tyres, they are good as they are. For a bit improved grip in the front, go for 305s, but forget about the spacers unless you are going to modify for significantly more aggressive look. And get your wheel alignment checked and adjusted by someone who knows what they are doing, a lot more important than changing rubber...

you won't have issues running 10mm spacers all around, especially if you're not lowered.

fyi, I'm lowered on KW HAS kit with wheels and tyres size indicated above and running 12mm spacers all around and I find no issues. by the way, my tyres are PZERO.

if you're planning on 305/30-20 tyres with 20x10.5 +19 wheels for rear, you should still be fine with 10mm spacers, especially if you're not lowered. (but with 305/30-20 PS4S, it may become a different story, so you'll just have to experiment to find what works for you)